public void TestECDH()
{
byte[] kA = new byte[X448.ScalarSize];
byte[] kB = new byte[X448.ScalarSize];
byte[] qA = new byte[X448.PointSize];
byte[] qB = new byte[X448.PointSize];
byte[] sA = new byte[X448.PointSize];
byte[] sB = new byte[X448.PointSize];
for (int i = 1; i <= 100; ++i)
{
// Each party generates an ephemeral private key, ...
Random.NextBytes(kA);
Random.NextBytes(kB);
// ... publishes their public key, ...
X448.ScalarMultBase(kA, 0, qA, 0);
X448.ScalarMultBase(kB, 0, qB, 0);
// ... computes the shared secret, ...
X448.ScalarMult(kA, 0, qB, 0, sA, 0);
X448.ScalarMult(kB, 0, qA, 0, sB, 0);
// ... which is the same for both parties.
Assert.IsTrue(Arrays.AreEqual(sA, sB), "ECDH #" + i);
}
}
public void TestConsistency()
{
byte[] u = new byte[X448.PointSize]; u[0] = 5;
byte[] k = new byte[X448.ScalarSize];
byte[] rF = new byte[X448.PointSize];
byte[] rV = new byte[X448.PointSize];
for (int i = 1; i <= 100; ++i)
{
Random.NextBytes(k);
X448.ScalarMultBase(k, 0, rF, 0);
X448.ScalarMult(k, 0, u, 0, rV, 0);
Assert.IsTrue(Arrays.AreEqual(rF, rV), "Consistency #" + i);
}
}
private static void CheckECDHVector(string sA, string sAPub, string sB, string sBPub, string sK, string text)
{
byte[] a = Hex.Decode(sA);
byte[] b = Hex.Decode(sB);
byte[] aPub = new byte[56];
X448.ScalarMultBase(a, 0, aPub, 0);
CheckValue(aPub, text, sAPub);
byte[] bPub = new byte[56];
X448.ScalarMultBase(b, 0, bPub, 0);
CheckValue(bPub, text, sBPub);
byte[] aK = new byte[56];
X448.ScalarMult(a, 0, bPub, 0, aK, 0);
CheckValue(aK, text, sK);
byte[] bK = new byte[56];
X448.ScalarMult(b, 0, aPub, 0, bK, 0);
CheckValue(bK, text, sK);
}
private static void CheckECDHVector(string sA, string sAPub, string sB, string sBPub, string sK, string text)
{
byte[] a = Hex.Decode(sA);
Assert.AreEqual(X448.ScalarSize, a.Length);
byte[] b = Hex.Decode(sB);
Assert.AreEqual(X448.ScalarSize, b.Length);
byte[] aPub = new byte[X448.PointSize];
X448.ScalarMultBase(a, 0, aPub, 0);
CheckValue(aPub, text, sAPub);
byte[] bPub = new byte[X448.PointSize];
X448.ScalarMultBase(b, 0, bPub, 0);
CheckValue(bPub, text, sBPub);
byte[] aK = new byte[X448.PointSize];
X448.ScalarMult(a, 0, bPub, 0, aK, 0);
CheckValue(aK, text, sK);
byte[] bK = new byte[X448.PointSize];
X448.ScalarMult(b, 0, aPub, 0, bK, 0);
CheckValue(bK, text, sK);
}
public X448PublicKeyParameters GeneratePublicKey()
{
byte[] publicKey = new byte[X448.PointSize];
X448.ScalarMultBase(data, 0, publicKey, 0);
return(new X448PublicKeyParameters(publicKey, 0));
}